patch-1.3.99 linux/drivers/net/slhc.h
Next file: linux/drivers/net/slip.c
Previous file: linux/drivers/net/slhc.c
Back to the patch index
Back to the overall index
- Lines: 188
- Date:
Thu Jan 1 02:00:00 1970
- Orig file:
v1.3.98/linux/drivers/net/slhc.h
- Orig date:
Wed Aug 10 19:26:18 1994
diff -u --recursive --new-file v1.3.98/linux/drivers/net/slhc.h linux/drivers/net/slhc.h
@@ -1,187 +0,0 @@
-#ifndef _SLHC_H
-#define _SLHC_H
-/*
- * Definitions for tcp compression routines.
- *
- * $Header: slcompress.h,v 1.10 89/12/31 08:53:02 van Exp $
- *
- * Copyright (c) 1989 Regents of the University of California.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms are permitted
- * provided that the above copyright notice and this paragraph are
- * duplicated in all such forms and that any documentation,
- * advertising materials, and other materials related to such
- * distribution and use acknowledge that the software was developed
- * by the University of California, Berkeley. The name of the
- * University may not be used to endorse or promote products derived
- * from this software without specific prior written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- *
- * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
- * - Initial distribution.
- *
- *
- * modified for KA9Q Internet Software Package by
- * Katie Stevens (dkstevens@ucdavis.edu)
- * University of California, Davis
- * Computing Services
- * - 01-31-90 initial adaptation
- *
- * - Feb 1991 Bill_Simpson@um.cc.umich.edu
- * variable number of conversation slots
- * allow zero or one slots
- * separate routines
- * status display
- */
-
-/*
- * Compressed packet format:
- *
- * The first octet contains the packet type (top 3 bits), TCP
- * 'push' bit, and flags that indicate which of the 4 TCP sequence
- * numbers have changed (bottom 5 bits). The next octet is a
- * conversation number that associates a saved IP/TCP header with
- * the compressed packet. The next two octets are the TCP checksum
- * from the original datagram. The next 0 to 15 octets are
- * sequence number changes, one change per bit set in the header
- * (there may be no changes and there are two special cases where
- * the receiver implicitly knows what changed -- see below).
- *
- * There are 5 numbers which can change (they are always inserted
- * in the following order): TCP urgent pointer, window,
- * acknowledgment, sequence number and IP ID. (The urgent pointer
- * is different from the others in that its value is sent, not the
- * change in value.) Since typical use of SLIP links is biased
- * toward small packets (see comments on MTU/MSS below), changes
- * use a variable length coding with one octet for numbers in the
- * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
- * range 256 - 65535 or 0. (If the change in sequence number or
- * ack is more than 65535, an uncompressed packet is sent.)
- */
-
-/*
- * Packet types (must not conflict with IP protocol version)
- *
- * The top nibble of the first octet is the packet type. There are
- * three possible types: IP (not proto TCP or tcp with one of the
- * control flags set); uncompressed TCP (a normal IP/TCP packet but
- * with the 8-bit protocol field replaced by an 8-bit connection id --
- * this type of packet syncs the sender & receiver); and compressed
- * TCP (described above).
- *
- * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
- * is logically part of the 4-bit "changes" field that follows. Top
- * three bits are actual packet type. For backward compatibility
- * and in the interest of conserving bits, numbers are chosen so the
- * IP protocol version number (4) which normally appears in this nibble
- * means "IP packet".
- */
-
-/* SLIP compression masks for len/vers byte */
-#define SL_TYPE_IP 0x40
-#define SL_TYPE_UNCOMPRESSED_TCP 0x70
-#define SL_TYPE_COMPRESSED_TCP 0x80
-#define SL_TYPE_ERROR 0x00
-
-/* Bits in first octet of compressed packet */
-#define NEW_C 0x40 /* flag bits for what changed in a packet */
-#define NEW_I 0x20
-#define NEW_S 0x08
-#define NEW_A 0x04
-#define NEW_W 0x02
-#define NEW_U 0x01
-
-/* reserved, special-case values of above */
-#define SPECIAL_I (NEW_S|NEW_W|NEW_U) /* echoed interactive traffic */
-#define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U) /* unidirectional data */
-#define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
-
-#define TCP_PUSH_BIT 0x10
-
-/*
- * data type and sizes conversion assumptions:
- *
- * VJ code KA9Q style generic
- * u_char byte_t unsigned char 8 bits
- * u_short int16 unsigned short 16 bits
- * u_int int16 unsigned short 16 bits
- * u_long unsigned long unsigned long 32 bits
- * int int32 long 32 bits
- */
-
-typedef unsigned char byte_t;
-typedef unsigned long int32;
-
-/*
- * "state" data for each active tcp conversation on the wire. This is
- * basically a copy of the entire IP/TCP header from the last packet
- * we saw from the conversation together with a small identifier
- * the transmit & receive ends of the line use to locate saved header.
- */
-struct cstate {
- byte_t cs_this; /* connection id number (xmit) */
- struct cstate *next; /* next in ring (xmit) */
- struct iphdr cs_ip; /* ip/tcp hdr from most recent packet */
- struct tcphdr cs_tcp;
- unsigned char cs_ipopt[64];
- unsigned char cs_tcpopt[64];
- int cs_hsize;
-};
-#define NULLSLSTATE (struct cstate *)0
-
-/*
- * all the state data for one serial line (we need one of these per line).
- */
-struct slcompress {
- struct cstate *tstate; /* transmit connection states (array)*/
- struct cstate *rstate; /* receive connection states (array)*/
-
- byte_t tslot_limit; /* highest transmit slot id (0-l)*/
- byte_t rslot_limit; /* highest receive slot id (0-l)*/
-
- byte_t xmit_oldest; /* oldest xmit in ring */
- byte_t xmit_current; /* most recent xmit id */
- byte_t recv_current; /* most recent rcvd id */
-
- byte_t flags;
-#define SLF_TOSS 0x01 /* tossing rcvd frames until id received */
-
- int32 sls_o_nontcp; /* outbound non-TCP packets */
- int32 sls_o_tcp; /* outbound TCP packets */
- int32 sls_o_uncompressed; /* outbound uncompressed packets */
- int32 sls_o_compressed; /* outbound compressed packets */
- int32 sls_o_searches; /* searches for connection state */
- int32 sls_o_misses; /* times couldn't find conn. state */
-
- int32 sls_i_uncompressed; /* inbound uncompressed packets */
- int32 sls_i_compressed; /* inbound compressed packets */
- int32 sls_i_error; /* inbound error packets */
- int32 sls_i_tossed; /* inbound packets tossed because of error */
-
- int32 sls_i_runt;
- int32 sls_i_badcheck;
-};
-#define NULLSLCOMPR (struct slcompress *)0
-
-#define __ARGS(x) x
-
-/* In slhc.c: */
-struct slcompress *slhc_init __ARGS((int rslots, int tslots));
-void slhc_free __ARGS((struct slcompress *comp));
-
-int slhc_compress __ARGS((struct slcompress *comp, unsigned char *icp,
- int isize, unsigned char *ocp, unsigned char **cpp,
- int compress_cid));
-int slhc_uncompress __ARGS((struct slcompress *comp, unsigned char *icp,
- int isize));
-int slhc_remember __ARGS((struct slcompress *comp, unsigned char *icp,
- int isize));
-int slhc_toss __ARGS((struct slcompress *comp));
-
-void slhc_i_status __ARGS((struct slcompress *comp));
-void slhc_o_status __ARGS((struct slcompress *comp));
-
-#endif /* _SLHC_H */
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov
with Sam's (original) version of this